单选题：Suppose there is a virtual memory system. A process is allocated

Suppose there is a virtual memory system. A process is allocated 3 frames and FIFO page-replacement algorithm is used. What is the number of page faults if the reference string is 1、2、3、4、1、2、5、1、2、3、4、5、6?@[D](1)
A. 7
B. 8
C. 9
D. 10





A.7
B.8
C.9
D.10


答案：D